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firewall blocking of loopback connection

Hi,

My question, in short, is:

Are software firewalls in their default configurations likely to block a connection from a program *to itself*?

Background:

I am working on a thick-client application that serves a lot of content as locally generated and modified web pages.

I've embedded a webserver in that client so that it serves up pages like http://localhost:/path/to/content/.After loading the pages AJAX is used to update the pages.

This approach provides a lot of functionality I want, but I want to avoid any problems with end-users' firewalls blocking the localhost connection, or annoying them with warning messages.

I'm sure that these connections *could* be blocked -- my question is whether such connections are likely to be blocked. For example, would they be blocked with the default configurations of popular firewalls. First of all I'm interested in {Windows XP, Windows Vista} x {Windows Firewall, Norton Firewall, ...}. But I'm also interested in Mac or Linux data.

Thanks a lot, David

Reply to
davidlmontgomery
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The products you're talking about are not FW(s), at best, they are packet filters. The Loopback IP shouldn't be blocked, and I know XP's and Vista's FW(s)/packet filters have no rules established to do this. Some of these other 3rd party solutions shouldn't be blocking on the Loopback IP either, but I guess you'll have to test your solution against them.

Reply to
Mr. Arnold

In my experience, sadly, they do. And because they shouldn't, it's obvious that they're ridicolously misconfigured by default.

Reply to
Sebastian G.

Not sure about how likely that is, but some Personal Firewalls do that, yes. However, the packet filters that come with the operating systems (Windows Firewall, ipfw, netfilter, ...) don't.

cu

59cobalt
Reply to
Ansgar -59cobalt- Wiechers

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